Thor, or should that be Zeus?

[Chaz]

Chaz I am afraid that the choice has to be yours alone. Are you using it to hold threading rod in a hole or bolt anchors?

I have 2 requirements. The first is to hold M12 nuts in place that allow me to tighten the bolts holding the rails in place.

Secondary is similar where ill either sink nuts for holding and mount hardware the same way (motor mounts etc) or where Ill epoxy thread bar in place. My preference is to sink the nuts so I can use bolts from the top.